JPH07129970A - Device for reproducing disk - Google Patents

Abstract

PURPOSE:To eliminate an unwanted vibration component incorporated in drive displacement and to prevent the omission of the data due to out-of-track by connecting an optical pickup means and a driving means through a viscoelastic substance. CONSTITUTION:By a notched part 10 formed on a rotary shaft 7 side of an optical pickup 3, the shaft 7 inserted into the pickup 3 is exposed. A rack plate 11 covering the notched part 10 is provided with an engage part engaging with the thread cutter grave of the shaft 7. By the way, the rack plate 11 is fixed to the pickup 3 through a silicon rubber 13. The fixation is performed by respectively applying adhesive material between the rack plate 11, the silicon rubber 13 and the pickup 3. When the shaft 7 is rotated by a stepping motor 8, the pickup 3 is moved in the radial direction of a disk through the engage part 12, the rack plate 11 and the silicon rubber 13. Thus, when the motor 8 is driven by one step, the vibration of the motor 8 is absorbed by the rubber 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a CD player,
The present invention relates to a disc reproducing device such as a magneto-optical disc player.

[0002]

2. Description of the Related Art Conventionally, in a magneto-optical disk player as disclosed in, for example, Japanese Patent Laid-Open No. 63-44329, a laser beam spot must be accurately tracked with respect to disk surface deflection and eccentricity. Focus servo and tracking servo are provided. A feed servo for moving the optical pickup in the radial direction of the disc is also provided in association with the tracking servo.

Feeding is performed by connecting a stepping motor to a threaded rotating shaft, engaging a rack attached to an optical pickup with the rotating shaft, and driving the stepping motor. I am trying.

By the way, the relationship between the tracking servo and the feed servo is as follows. That is, for example, when the spiral tracks are continuously connected and reproduced, the beam spot gradually moves from the neutral point of the track actuator, and when the deviation exceeds the beam spot movable range of the track actuator, the stepping motor is moved. Is driven one step to feed in a direction to reduce this deviation.

[0005]

In the above configuration (state in which a stepping motor is connected to the optical pickup),
When the stepping motor is driven by one step, the transient response characteristic of the rotation angle of the shaft is oscillatory as shown in FIG. 3 (a), and it is the friction between the rotation shaft and the optical pickup that contributes to the damping. Occupy.

Therefore, this vibration is directly transmitted to the optical pickup. At this time, the moving speed of the optical pickup at the time of vibration is high, and the moving speed of the beam spot by the track actuator relative to the optical pickup is also high, so the tracking becomes unstable, and in some cases, the track is deviated and the data is lost. There were things.

[0007]

DISCLOSURE OF THE INVENTION A disc reproducing apparatus of the present invention comprises an optical pickup means for reading out information recorded on a disc and a drive means for moving the optical pickup means in the radial direction of the disc. ,
The optical pickup means and the driving means are connected via a viscoelastic material.

[0008]

Since the present invention is configured as described above, it is possible to transmit the driving force to the optical pickup means by reducing unnecessary vibration components contained in the driving displacement of the driving device to the extent that they do not hinder the reproduction. You can

[0009]

Embodiments of the present invention will be described with reference to the drawings.
In FIG. 1, (1) is a magneto-optical disk in which recording / reproducing tracks (2) are spirally arranged at a pitch of 1.6 μm,
Reference numeral (3) is an optical pickup for irradiating a track (2) of the magneto-optical disk (1) with a laser beam spot (5) formed by an objective lens (4) and reading out data recorded on the track. Objective lens (4)
It has a movable part (6) including. The movable portion (6) can be two-dimensionally moved by a focus actuator and a tracking actuator (not shown), which enables focus and tracking control. (7) is a threaded rotary shaft, which is connected to the stepping motor (8). The rotary shaft (7) is inserted through the optical pickup (3).
(9) is a guide rail for guiding the optical pickup (3) together with the rotary shaft (7) in the radial direction of the disc, and (10) is on the rotary shaft (7) side of the optical pickup (3). The formed notch portion exposes the rotary shaft (7) inserted through the optical pickup (3). Reference numeral (11) is a rack plate that covers the cutout portion, and has a meshing portion (12) that meshes with the threaded groove of the rotating shaft (7) as shown in FIG. By the way, the rack plate (11) is fixed to the optical pickup (3) through a silicone rubber (13). This fixing is performed by applying an adhesive to each of the rack plate (11), the silicone rubber (13) and the optical pickup (3).

Thus, in the above structure, when the rotating shaft (7) is rotated by the stepping motor (8), the meshing portion (12), the rack plate (11), and the silicone rubber (13).
The optical pickup (3) moves in the radial direction of the disk via the.

Thus, the stepping motor (8) is set to 1
When the step drive is performed, the silicone rubber absorbs the vibration of the stepping motor (8), and the response characteristic becomes as shown in FIG. 3 (b), and the acceleration, speed, and overshoot amount are all greatly reduced compared to the conventional case. The occurrence of track slippage could be significantly reduced.

Further, according to the present invention, the conventional problems can be solved without constructing any friction or viscosity between the optical pickup (3) and the guide rail (9) and the rotating shaft (7). Therefore, the power for driving the optical pickup (3) is the same as the conventional one, and the same performance as the conventional one can be secured with respect to the seek time and the like.

By the way, in the above structure, when seeking, that is, by continuously driving the stepping motor (8),
When the optical pickup (3) is moved to a predetermined position, the silicone rubber (1
The deformation amount of 3) becomes too large, and the stepping motor (8)
There was a problem such as the optical pickup (3) vibrating when stopped. Therefore, in the present invention, as shown in FIG. 3, the bent portions (14) (1) are provided at both ends of the rack plate (11).
4) is provided and the deformation amount of the silicone rubber (13) is regulated to solve this problem.

During this seek, of course, the data is not read, and the data is read after the desired track is detected with stable vibration. There is no problem if the pickup (3) vibrates.

Although silicon rubber is used as the viscoelastic material in the above-described embodiments of the present invention, the viscoelastic material is not limited to this and other viscoelastic materials may be used.

In the embodiment of the present invention, the optical pickup is an integral type optical pickup including an actuator and an optical system, but it may be a separate type in which the optical system is fixed and only the actuator portion moves.

[0017]

Since the present invention is constructed as described above, unnecessary vibration components included in the driving displacement of the driving means can be removed, and therefore data loss due to track deviation can be prevented.

[Brief description of drawings]

FIG. 1 is a perspective view of a main part of a disc reproducing apparatus of the present invention.

FIG. 2 is a side view of the main part of the disk reproducing device.

FIG. 3 is a time displacement diagram of the same optical pickup.

[Explanation of symbols]

 3 Optical pickup 7 Rotation axis 8 Stepping motor 11 Rack plate 12 Engagement portion 13 Silicon rubber

Front Page Continuation (72) Inventor Kenji Mita 3-201 Minamiyoshikata, Tottori City, Tottori Prefecture Tottori Sanyo Electric Co., Ltd.

Claims (1)

[Claims] 1. A viscoelastic material comprising optical pickup means for reading information recorded on a disc and drive means for moving the optical pickup means in the radial direction of the disc, wherein the optical pickup means and the drive means are viscoelastic materials. A disc reproducing apparatus, characterized in that it is configured to be connected via.